// vertex shader

uniform mat4 mvpmatrix;          // mvp矩阵
attribute highp vec3 position;   // 输入的顶点位置
attribute highp vec3 color;      // 输入颜色
attribute highp vec2 a_texcoord; // 纹理坐标

varying highp vec3 v_color;
varying highp vec2 v_texcoord;

void main() {
  gl_Position = mvpmatrix * vec4(position, 1.0);
  v_color = color;
  v_texcoord = a_texcoord;
}
